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Single-atomic metal catalysts are attractive for green chemistry in terms of their outstanding catalytic performance and savings in precious metal usage owing to maximized metal utilization, including anode catalysts in polymer electrolyte fuel cells (PEFCs). Heteroatom-doped porous carbons are extensively used as supports, where the heteroatoms contribute to the immobilization of single-atomic metals. However, high-content doping of heteroatoms, especially sulphur (S), into carbon supports is still challenging because S species can be readily desorbed during heat treatment. Herein, we present a bottom-up fabrication approach for S-rich porous carbons from molecular precursors via a thermal polymerization process. A simple carbonization of molecules with thermally stable S-containing building blocks and polymerizable ethynyl moieties at 900 °C yields microporous carbon materials with record-high S content (over 15 wt%). The abundant S species function as an effective anchoring site for single-atomic platinum (Pt) species. Toward anode catalysts in PEFCs, the prepared single-atomic Pt catalysts efficiently promote the electrochemical hydrogen oxidation reaction, whose activity is comparable to that of commercial Pt/C, despite the significantly low Pt loading amount. [ABSTRACT FROM AUTHOR]

Aerobic oxidative dehydrogenation of amines to imines by thiol‐modified Pd nanoparticle (NP) catalysts on carbon supports is reported herein. Whereas conventional non‐modified Pd NP catalysts are nearly inactive, the carbon‐supported Pd catalysts modified with thiol ligands efficiently catalyze the reaction with high selectivity. Kinetic studies and DFT calculations reveal that the rate‐limiting imine product desorption step is significantly boosted on the thiol ligands‐modified Pd surface compared to the non‐modified Pd surface due to the steric hindrance of the ligands. Furthermore, the catalytic activity is dramatically enhanced in the presence of both pyrene‐functionalized thiol modifiers and graphene‐based carbon supports; 96 % conversion is attained after 4 h at 110 °C. The π–π interactions between pyrene groups and the highly crystallized carbon surface suppress the leaching of ligands, which offers improved catalyst stability even under O2 atmosphere at 110 °C, thereby resulting in high activity. [ABSTRACT FROM AUTHOR]

Keywords: Dehydrogenation; Heterogeneous catalysis; Pd nanoparticles; - interaction; Surface modification EN Dehydrogenation Heterogeneous catalysis Pd nanoparticles - interaction Surface modification 5834 5834 1 12/07/20 20201204 NES 201204 B The Front Cover b shows Pd nanoparticle catalysts modified with pyrene-thiol ligands on carbon supports for aerobic oxidative dehydrogenation of amines to imines. In their Communication, T. Yoshii et al. experimentally and theoretically demonstrate that the rate-limiting imine product desorption is boosted as a result of the steric hindrance of the ligands, and the catalytic stability is significantly improved by the - interactions between catalyst and support, which make this material an active and stable catalyst for the amine dehydrogenation reaction. Dehydrogenation, Heterogeneous catalysis, Pd nanoparticles, - interaction, Surface modification. [Extracted from the article]